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排序方式: 共有422条查询结果,搜索用时 15 毫秒
41.
Haq IU Khan MA Muneer B Hussain Z Afzal S Majeed S Rashid N Javed MM Ahmad I 《Biotechnology letters》2012,34(9):1703-1709
A genomic DNA fragment, encoding a thermotolerant β-glucosidase, of the obligate anaerobe Thermotoga petrophila RKU-1 was cloned after PCR amplification into Escherichia coli strain BL21 CodonPlus. The purified cloned enzyme was a monomeric, 51.5?kDa protein (by SDS-PAGE) encoded by 1.341?kb gene. The estimated K (m) and V (max) values against p-nitrophenyl-β-D-glucopyranoside were 2.8?mM and 42.7?mmol?min(-1)?mg(-1), respectively. The enzyme was also active against other p-nitrophenyl substrates. Possible catalytic sites involved in hydrolyzing different p-nitrophenyl substrates are proposed based on docking studies of enzyme with its substrates. Because of its unique characters, this enzyme is a potential candidate for industrial applications. 相似文献
42.
Background
Most epidemiological studies exploring the association between smokeless tobacco (SLT) use and coronary heart disease (CHD) have been in Western populations, and have focused on SLT products used in those countries. Few studies come from South Asian countries. Our objective was to determine the association between SLT use and CHD among non-smoking adults in Bangladesh.Methods
A matched case-control study of non-smoking Bangladeshi adults aged 40–75 years was conducted in 2010. Incident cases of CHD were selected from two cardiac hospitals. Community controls, matched to CHD cases, were selected from neighbourhoods, and hospital controls were selected from outpatient departments of the same hospitals. The Rose Angina Questionnaire (RAQ) was also used to re-classify cases and controls.Results
The study enrolled 302 cases, 1,208 community controls and 302 hospital controls. Current use was higher among community controls (38%) compared to cases (33%) and hospital controls (32%). Current use of SLT was not significantly associated with an increased risk of CHD when community controls were used (adjusted OR 0.87, 95% CI 0.63–1.19), or when hospital controls were used (adjusted OR 1.00, 95% CI 0.63–1.60), or when both control groups were combined (adjusted OR 1.00, 95% CI 0.74–1.34). Risk of CHD did not increase with use of individual types except gul, frequency, duration, past use of SLT products, or using the RAQ to re-classify cases and controls. There was a significant association between gul use and CHD when both controls were combined (adjusted OR 2.93, 95% CI 1.28–6.70).Conclusions
There was no statistically significant association between SLT use in general and CHD among non-smoking adults in Bangladesh. Further research on the association between gul use and CHD in Bangladesh along with SLT use and CHD in other parts of the subcontinent will guide public health policy and interventions that focus on SLT-related diseases. 相似文献43.
Kazi S Shultz J Afzal J Johnson J Njiti VN Lightfoot DA 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,116(7):967-977
Soybean [Glycine max (L.) Merr.] cultivars show differences in their resistance to both the leaf scorch and root rot of sudden death syndrome
(SDS). The syndrome is caused by root colonization by Fusarium virguliforme (ex. F. solani f. sp. glycines). Root susceptibility combined with reduced leaf scorch resistance has been associated with resistance to Heterodera glycines HG Type 1.3.6.7 (race 14) of the soybean cyst nematode (SCN). In contrast, the rhg1 locus underlying resistance to Hg Type 0 was found clustered with three loci for resistance to SDS leaf scorch and one for
root infection. The aims of this study were to compare the inheritance of resistance to leaf scorch and root infection in
a population that segregated for resistance to SCN and to identify the underlying quantitative trait loci (QTL). “Hartwig”,
a cultivar partially resistant to SDS leaf scorch, F. virguliforme root infection and SCN HG Type 1.3.6.7 was crossed with the partially susceptible cultivar “Flyer”. Ninety-two F5-derived
recombinant inbred lines and 144 markers were used for map development. Four QTL found in earlier studies were confirmed.
One contributed resistance to leaf scorch on linkage group (LG) C2 (Satt277; P = 0.004, R
2 = 15%). Two on LG G underlay root infection at R8 (Satt038; P = 0.0001 R
2 = 28.1%; Satt115; P = 0.003, R
2 = 12.9%). The marker Satt038 was linked to rhg1 underlying resistance to SCN Hg Type 0. The fourth QTL was on LG D2 underlying resistance to root infection at R6 (Satt574;
P = 0.001, R
2 = 10%). That QTL was in an interval previously associated with resistance to both SDS leaf scorch and SCN Hg Type 1.3.6.7.
The QTL showed repulsion linkage with resistance to SCN that may explain the relative susceptibility to SDS of some SCN resistant
cultivars. One additional QTL was discovered on LG G underlying resistance to SDS leaf scorch measured by disease index (Satt130;
P = 0.003, R
2 = 13%). The loci and markers will provide tagged alleles with which to improve the breeding of cultivars combining resistances
to SDS leaf scorch, root infection and SCN HG Type 1.3.6.7.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
44.
45.
Sameera Al-Awadi M. Afzal S. Oommen 《The Journal of steroid biochemistry and molecular biology》2001,78(5)
When Bacillus stearothermophilus, a thermophilic bacterium isolated from the Kuwaiti desert, was incubated with exogenous progesterone for 24 h, three monohydroxylated metabolites were produced. 20α-Hydroxyprogesterone was the major metabolite produced in 60.8 relative percentage yield. The other two monohydroxylated metabolites were identified as 6β-hydroxyprogesterone and the rare 6α-hydroxyprogesterone in 21.0 and 13.6 relative percentage yields, respectively. A new metabolite 9,10-seco-4-pregnene-3,9,20-trione was isolated in 3.7 relative percentage yield. All metabolites were purified by preparative TLC and HPLC followed by their identification using 1H, 13C NMR and other spectroscopic data. 相似文献
46.
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48.
A new Streptomyces species is described for which the name S. maghwi is proposed. The organism is characterized by a pink mass of aerial mycelium, spiral spore chains, spores with smooth surfaces and a nonchromogenic vegetative mycelium. S. maghwi produces roflamycoin (Schlegel et al. 1981) formerly known as flavomycoin (Schlegel et al. 1971). The type strain of S. maghwi is deposited with CBS, Netherland. 相似文献
49.
50.
Almas Fakhrah Hassan Adeel Bibi Arfa Ali Masab Lateef Sadia Mahmood Tariq Rasheed Awais Quraishi Umar Masood 《Plant and Soil》2018,431(1-2):371-387
Plant and Soil - Extreme climate events, including flooding and prolonged drought, may establish long-lasting (legacy) effects on soil abiotic and biotic properties, potentially influencing soil... 相似文献